Syntax support: a if cond else b

[wangkuiyi]

During the prototyping of Go+Torch, I noticed many Python AI programmers use Python's form of C's ? :. For example

device = torch.cuda_device(0) if opt.cuda else torch.cpu_device()

This pattern is so commonly used by Python programmers that I am expecting that Go+ could have a match. Also, Go's way is really lengthy and might call torch.xxx_device twice.

device := torch.cpu_device()
if opt.cuda {
     device = torch.cuda_device(0)
}

If we want to avoid the possibility of twice calls, we'd have to adopt an even more lengthy way:

var device torch.Device
if opt.cuda {
     device = torch.cpu_device()
} else {
     device = torch.cuda_device(0)
}

I heart that Go Authors avoided the introduction of C's ? : syntax for some reason, but could we follow Python and give the ? : a more readable form.

[lolbinarycat]

This doesn't really look like go to me. This would make code easier to write, but at the cost of being harder to read. I also don't like the idea of overloading keywords like this. I think some variation of this that only works for variable initialization is worth consideration. But not this, and certainly not before we get some basic things implemented, like custom types.